Acoustic guitars are well known. They usually include a hollow body to which a neck is attached. The neck usually defines an angle with respect to the guitar top to allow for a comfortable string action, i.e. the distance between the strings and the neck.
Many neck attachment techniques have been developed in the past.
A traditional neck attachment technique uses a so-called Spanish neck, i.e. a neck that is one piece from the head to the foot inside the body of the guitar. The sides of the guitar are glued into slots cut in the heel of the neck. This type of neck attachment results in a very rigid assembly. However, it is not well suited to contemporary manufacturing since the neck is attached to the body at the beginning of the construction of the instrument, making it too bulky.
Another long standing neck attachment technique consists of making a dovetail assembly between the neck and the body. Traditionally, a dovetail tenon is made in the neck and a corresponding dovetail mortise is made in the body. While this joint is also very strong, it is very difficult to disassemble and the neck angle may be difficult to adjust since there are many mating surfaces.
Guitar makers recently began using mechanical fasteners, such as machine screws and threaded inserts, to attach the neck to the body. Generally, two inserts are installed in the heel of the neck and the machine screws are inserted from the inside of the body to attach the neck. While this neck attachment provides a strong back to forth support of the neck, it has been remarked that the lateral support is less than optimal. Indeed, the mechanical fasteners are aligned with the centerline of the neck and body, giving poor lateral support.